The Implications of Wildfires for Water Resources in the Bolivian Chiquitano Dry Forest: An Integrated Framework to Include Water in Forest Restoration Plans

Abstract:

One of the world’s largest and few remaining dry forest ecosystems, the Chiquitano forest is largely located in Bolivia, between the Amazon and La Plata basins. Fires occur every year in the area as part of the natural dynamics of the ecosystem and due to regular pasture burning. In 2019, intentional fires spiraled out of control, resulting in a catastrophic “megafire” with approximately 3.6 million hectares burned. There are strong indications that events of this intensity and magnitude are happening more frequently as a result of climate change. Though regional and national restoration plans aim to address the impacts of increased fires and deforestation on the land cover and biodiversity of the Chiquitania region, limited consideration is given to potential changes in regional water balances and the availability of water resources. This is especially problematic in a context of growing water demands for farming and the development of groundwater resources. This study proposes a general framework for evaluating fire impacts and prioritizing restoration efforts at the watershed level. In the first part, ESA and NASA remote sensing products of land cover and burned areas were processed to map temporal and spatial changes in the Chiquitano forest cover, as well as the yearly and cumulative burned area between 2001 and 2019. The resulting dataset was combined with maps of the region’s watersheds in QGIS and Tableau to create a visualization at the watershed scale. The study found that Chiquitania fires are primarily associated with forest cover losses and the advancing of the agricultural frontier. The conversion of forests to agricultural areas has been progressing steadily since 2001 and more rapidly since 2016. However, fires do not automatically mean that burned forest area is lost and permanently converted to agriculture. The results demonstrate the utility of visualizing fire activity and potential permanent forest loss at the watershed scale. These are discussed in terms of (a) implications for conservation of intact Chiquitano forest, and (b) opportunities to support local authorities and policymakers with integrated land and water resources management. Our framework will serve as the foundation to define priority watersheds for which a set of comprehensive water balance studies will be developed in the future.